Met Office Winter Forecast Predicts Potential UK Freeze Due to Weakening Polar Vortex

The Met Office has released its winter weather forecast for the UK, covering October to December. This season may see a shift from milder temperatures to notably chillier conditions, attributed to a weakening polar vortex. Meteorologists define the meteorological winter as beginning on December 1 and lasting until February 28, while astronomical winter starts on December 21 and continues until March 20.

Impact of the Weakening Polar Vortex

The polar vortex is a large system of winds in the stratosphere, located approximately 30 miles (50 km) above the earth. Changes in the strength of this phenomenon directly affect winter weather, particularly in terms of the jet stream, which is situated around six miles above the ground. This air channel plays a significant role in transporting weather systems from the Atlantic Ocean toward the UK.

According to John Hammond, co-developer of the Vacay Weather app, the weakening of the polar vortex can lead to a release of colder Arctic air into the UK. He acknowledges that while very cold winters are becoming increasingly rare, occasional cold snaps can still occur. Hammond notes that we are currently in a phase of the Quasi Biennial Oscillation, which may make the polar vortex more susceptible to weakening this winter.

Forecast and Expectations

The Met Office forecasts suggest that from December onwards, temperatures may fall below the seasonal norm. Alongside the potential for colder conditions, the agency predicts “near-average” rainfall and wind speeds throughout the winter months.

• Meteorological Winter: December 1 to February 28
• Astronomical Winter: December 21 to March 20
• Temperature Outlook: Lower than average temperatures anticipated by December
• Rainfall and Wind: Near-average levels expected

The Met Office highlights a 55% chance of temperatures being below the norm for this period, which is marginally lower than average. In summary, while mild spells may occur, there is an increasing likelihood of colder weather due to incoming northwesterly and northerly airflows later in the season. The ongoing analysis of the polar vortex suggests that winter hazards could be more common than usual during this time.